A variety of optoelectronic devices are packaged devices which include a photodetector (PD) and at least one light source that is operated under a vacuum. Conventional MFAC and MFAM packages include a vertically stacked structure inside a package material including a bottom die as a support having electrical traces and at least one light source (e.g., a laser die such as a vertical-cavity surface-emitting laser (VCSEL)) mounted thereon, a first cavity die on the bottom die providing a cavity over the light source, and an optics die on the first cavity die.
The electrical traces on the bottom die connect an external driver which drives the light source and includes traces configured for a resistive heater element, such as to provide heat to heat the light source die to a temperature of about 60 to 80° C. A second cavity die is on the optics die, other optical device(s) (e.g., a polarizer) is on the second cavity die, and a photodetector (PD) die is on a dielectric substrate over the other optical device(s). The package is a vacuum sealed package.